Drags continue even if the layout shifts on drag start - #61527
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This CL fixes a bug with drag and drop where a drag will not happen if the `dragstart` listener removes the drag source or generates a layout shift. When a drag starts, blink will try hit-testing the drag start location *after* the `dragstart` event is fired to determine the dragged element and create an overlay image for it. If listeners of the `dragstart` event caused a layout shift or removed the element from the document, then the hit test will fail and the drag operation will be aborted. This CL reorders the steps in the sequence to create a drag by moving the hit testing and image overlay generation to *before* the `dragstart` event is fired in `PopulateDragDataTransfer`. With this change, even if `dragstart` removes an element from the document, the user will still be presented with the correct drag overlay image. In addition to the new tests in this CL, these changes were manually verified in the WPT remove/ and overlay/ drag and drop directories to confirm correct UA behavior. Bug: 434130455 Change-Id: I84bab2edb505b113e8a9481109f196d225d77718 Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/7748202 Reviewed-by: Mustaq Ahmed <mustaq@chromium.org> Commit-Queue: Gaston Rodriguez <gastonr@microsoft.com> Cr-Commit-Position: refs/heads/main@{#1668792}
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This CL fixes a bug with drag and drop where a drag will not happen if
the
dragstartlistener removes the drag source or generates a layoutshift.
When a drag starts, blink will try hit-testing the drag start location
after the
dragstartevent is fired to determine the dragged elementand create an overlay image for it. If listeners of the
dragstartevent caused a layout shift or removed the element from the document,
then the hit test will fail and the drag operation will be aborted.
This CL reorders the steps in the sequence to create a drag by moving
the hit testing and image overlay generation to before the
dragstartevent is fired in
PopulateDragDataTransfer. With this change, even ifdragstartremoves an element from the document, the user will stillbe presented with the correct drag overlay image.
In addition to the new tests in this CL, these changes were manually
verified in the WPT remove/ and overlay/ drag and drop directories to
confirm correct UA behavior.
Bug: 434130455
Change-Id: I84bab2edb505b113e8a9481109f196d225d77718
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/7748202
Reviewed-by: Mustaq Ahmed <mustaq@chromium.org>
Commit-Queue: Gaston Rodriguez <gastonr@microsoft.com>
Cr-Commit-Position: refs/heads/main@{#1668792}